One animation has been defined to animate the height of a rectangle. Ruler lines and text are provided
to help show what the correct behavior is. The red text shows the values for the 'calcMode' and 'keyTimes' attributes. The
black text and ruler lines help show the size and movement of the rectangle over time.

This animation shows calcMode="spline". Between time 4 seconds and 8 seconds, the animation displays an ease-in/ease-out approach
instead of a constant linear approach which would have been the case if calcMode ad been linear instead.